Bug: adding externals with tag reference generates an error

[francescopitzalis]

Steps to reproduce

mkdir test-git-externals
cd test-git-externals/
git init
echo "test" > README.md
git externals add --tag=v4.4 https://github.com/torvalds/linux.git Makefile Makefile
git add README.md git_externals.json
git commit -m "First commit"
git externals update

Expected outcome

The repository is cloned in .git_externals and the symlink is created in the root dir of the repository

Actual outcome

This stack trace:

Traceback (most recent call last):
  File "/usr/local/bin/git-externals", line 9, in <module>
    load_entry_point('git-externals==0.5.0', 'console_scripts', 'git-externals')()
  File "/Library/Python/2.7/site-packages/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/Library/Python/2.7/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/Library/Python/2.7/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/Library/Python/2.7/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/Library/Python/2.7/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/Library/Python/2.7/site-packages/git_externals/cli.py", line 106, in gitext_update
    externals_sanity_check()
  File "/Library/Python/2.7/site-packages/git_externals/git_externals.py", line 241, in externals_sanity_check
    foreach_externals(root, registry_add, recursive=True)
  File "/Library/Python/2.7/site-packages/git_externals/git_externals.py", line 156, in foreach_externals
    callback(rel_url, ext_path, externals[rel_url])
  File "/Library/Python/2.7/site-packages/git_externals/git_externals.py", line 239, in registry_add
    registry[url].add(ExtItem(ext['branch'], ext['ref'], path, ext.get('name', '')))
KeyError: u'branch'

[naufraghi]

Hi @francescopitzalis, thanks for reporting.

git-externals is in frozen mode, we are migrating our internal repos to a new tool that requires some step more (no partial repo support) but has some extra feature too: quark.